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Exploring high school students’ perceptions of solar energy and solar cells Padmini Kishore La Mirada High School, La Mirada, CA James Kisiel California State University, Long Beach Received 11 July 2012; Accepted 26 April 2013 Doi: 10.12973/ijese.2013.216a Although studies examining student understanding of key concepts are common throughout the science education literature, few have examined science concepts linked to conservation or environmental issues such as global warming and alternati- ve energy. How students make sense of these complex concepts has the potential to influence their role as future decision-makers; it therefore becomes important to explore this baseline knowledge, especially when such concepts receive limited dis- cussion in typical school curricula. In this study, a questionnaire incorporating both multiple choice and open-ended responses was administered to high school sophomores to better understand their conceptions of solar energy and photovoltaic cells. Analysis revealed that while students reported familiarity with photovoltaic cells, there was confusion as to how they actually worked. An underlying misconception involved the roles of light or heat from the sun in the function of these solar cells. Implications for instruction and future research are suggested. Keywords: energy misconceptions, environmental science, photovoltaic cell, solar energy Exploring High School Students’ Perceptions of Solar Energy and Solar Cells If we wish to develop new advocates for the environment, who look critically at current issues such as global warming and carbon emissions impacts, we might consider targeting high school students on the threshold of becoming drivers (and thereby extensive fuel consumers.) Unfortunately such environment- and conservation-related topics receive limited explicit attenti- on in K-12 state and national science standards. The National Science Education Standards do mention several energy-related topics, such as energy transfer, energy as a fuel that can be stored, used and exhausted, global climate and chemical reactions that result in urban smog (NRC, 1996), yet environmental science is still not considered an important subject on par with biology and chemistry (Coyle, 2005). In the Science Content Standards for California Public Schools, solar energy is mentioned through the discussion of food webs as it is transformed to other forms International Journal of Environmental & Science Education (2013), 8, 521-534 ISSN 1306-3065 Copyright © 2006-2013 by iSER, International Society of Educational Research. All Rights Reserved.

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International Journal of Environmental & Science Education

Vol. 3 , No. 3 , July 2008, xx-xx

Exploring high school students’ perceptions of solar energy and solar cells

Padmini Kishore La Mirada High School, La Mirada, CA

James Kisiel California State University, Long Beach

Received 11 July 2012; Accepted 26 April 2013

Doi: 10.12973/ijese.2013.216a

Although studies examining student understanding of key concepts are common

throughout the science education literature, few have examined science concepts

linked to conservation or environmental issues such as global warming and alternati-

ve energy. How students make sense of these complex concepts has the potential to

influence their role as future decision-makers; it therefore becomes important to

explore this baseline knowledge, especially when such concepts receive limited dis-

cussion in typical school curricula. In this study, a questionnaire incorporating both

multiple choice and open-ended responses was administered to high school

sophomores to better understand their conceptions of solar energy and photovoltaic

cells. Analysis revealed that while students reported familiarity with photovoltaic

cells, there was confusion as to how they actually worked. An underlying

misconception involved the roles of light or heat from the sun in the function of these

solar cells. Implications for instruction and future research are suggested.

Keywords: energy misconceptions, environmental science, photovoltaic cell,

solar energy

Exploring High School Students’ Perceptions of Solar Energy and Solar Cells

If we wish to develop new advocates for the environment, who look critically at current issues

such as global warming and carbon emissions impacts, we might consider targeting high school

students on the threshold of becoming drivers (and thereby extensive fuel consumers.)

Unfortunately such environment- and conservation-related topics receive limited explicit attenti-

on in K-12 state and national science standards. The National Science Education Standards do

mention several energy-related topics, such as energy transfer, energy as a fuel that can be stored,

used and exhausted, global climate and chemical reactions that result in urban smog (NRC,

1996), yet environmental science is still not considered an important subject on par with biology

and chemistry (Coyle, 2005). In the Science Content Standards for California Public Schools,

solar energy is mentioned through the discussion of food webs as it is transformed to other forms

International Journal of Environmental & Science Education

(2013), 8, 521-534

ISSN 1306-3065 Copyright © 2006-2013 by iSER, International Society of Educational Research. All Rights Reserved.

522 Kishore & Kisiel

of energy (grades 4 and 6), but little is mentioned about its utilities as an alternative source of

energy (CDE, 1998). In California, the Education and Environment Initiative (EEI) has led to the

development of standards and the design of curriculum components that examine the interaction

and interdependence of human societies and natural systems (California Environmental Protecti-

on Agency, 2007). The emergence of such initiatives, in California and other states, suggests that

environmental education may soon become a mandatory component of public education, but the

extent to which such efforts make their way into an already crowded curriculum remains to be

seen.

Nevertheless, as society begins to consider more seriously the alternatives to fossil fuels

and the growth of ‘green’ industry, understanding of the science and technology related to energy

becomes more and more important. Not only does this include awareness of the impacts of using

such energy sources, but also understanding just how these different alternatives actually work.

In their investigation of museum visitor’s conception of environmental radiation and the

effectiveness of a related exhibition, Henriksen and Jorde (2001) questioned whether providing a

stronger scientific basis for decision-making related to concepts such as ionizing radiation and

global warming (via an exhibition), could change or strengthen positions on relevant environ-

mental issues. Their study indicated that the exhibition did indeed help to influence visitor un-

derstanding and subsequently led to a decrease in ‘opinion-based’ reasoning for environmental

stance. For the same reason, we would suggest that students who understand the basic principles

behind photovoltaic cells and other alternate energy sources (such as wind turbines) would be

more likely to be better informed in their decision-making (at both personal and public levels.) In

addition, we feel that such perspectives would help students to be better informed regarding their

potential to become part of a new workforce surrounding these ‘green’ technologies.

The Challenge of Conceptual Change

Because students already have ideas about how the natural world works, high school science

teachers often face a daunting question: “What do students know and how can I use that informa-

tion to support instruction?”. Indeed, a constructivist perspective on learning suggests that

humans generally construct an understanding of the world based on observations and experiences

inside and out of school. This understanding is subsequently used to organize ideas, make

predictions, and provide explanations that may or may not be consistent with established scienti-

fic knowledge. Consequently, upon entering the science classroom, students often interpret scien-

tific (and environment-related) phenomenon in ways that are radically different from the

teacher’s or the scientist’s perspective (Driver, Squires, Rushworth, & Wood-Robinson, 1994).

Changing students’ minds and helping them more deeply understand a phenomenon that is

inconsistent with their current knowledge structure requires conceptual change. Such changes can

be as simple as helping students re-organize concepts (e.g. humans are not different from

mammals, but rather are a kind of mammal) to more complicated restructuring of longstanding

networks that are generally resistant to change (NRC, 2007). Such efforts first require a better

picture of what conceptual structures currently exist; this then allows us to better strategize how

best to build on or revise current knowledge in ways that lead to more effective predictions and

explanations of the natural world.

Prior Knowledge about Energy Alternatives

Research on student understanding of renewable or alternate energy sources is almost non-

existent (see for instance Solomon, 1985), although several studies have examined public

attitudes related to alternative energy (see for instance Bang et al., 2000; Kinsey, Haines & Peter-

Perceptions of Solar Energy and Solar Cells 523

son, 2003; Krohn & Damborg, 1999). In 2002, the National Environmental Education and Trai-

ning Foundation (NEETF) published its tenth annual national report card on energy knowledge,

attitudes and behavior. The report, based on randomly selected telephone interviews with 1,503

adults (over age 18), suggested that a majority of Americans (75%) rated themselves as having a

lot of knowledge about energy issues and problems. In addition, approximately 90% of the

respondents in the NEETF survey indicated that energy conservation should be taught in our

schools. Yet when asked to complete a short ‘energy awareness’ quiz, only 12% were able to

pass the quiz. For instance, only 36% of adult participants were able to identify ‘burning oil, coal

or wood’ as the primary source of energy in the United States. The report suggests that while

Americans generally respond positively to the importance of energy alternatives and

conservation, they overestimate their understanding of these concepts.

The National Energy Education Development (NEED) project provides educational ma-

terials and a weeklong training for teachers participating in special grant-funded workshops. A

variety of hands-on educational kits and information about other resources and suppliers is made

available to every teacher. In order to assess the effectiveness of the program, NEED has

conducted pre- and post-program surveys for participating students (NEED, 2003). The polls are

designed for different grade levels (primary, elementary, intermediate, secondary) and test stu-

dent understanding of basic concepts related energy and resource use. Although the NEED sur-

vey was originally designed as a pre/post-test to examine the effectiveness of a particular curricu-

lum, examination of the pre-test findings do provide a useful baseline of student understanding.

As with the adults, students were generally unable to correctly identify which energy source

produced most of our electricity (25% of elementary/middle school students, 50% of high school

students). Although the NEED survey does provide some information regarding student unders-

tanding of these concepts, it is important to recognize that it consists of multiple choice questions

with specific answers provided. The NEED assessment does not allow for student explanations,

nor does the report indicate which incorrect answers were common— both pieces of information

that would help identify student misconceptions. Furthermore, although some of the NEED pro-

gramming involves discussion of solar energy and solar (photovoltaic) cells, none of the poll

questions specifically addressed the student knowledge of solar cells, nor how this technology

actually works.

Misconceptions Related to Energy

Understanding how energy alternatives work is further complicated by the abstract nature of

energy itself, as well as the everyday use of the term. For instance, although a scientific definition

of energy might be ‘the ability to do work’ or 'the ability of matter to cause changes' (Stepans,

2003), the term is used more liberally in common language, sometimes described in terms of fuel,

activity level or even a person’s mood. Understanding these scientific definitions is difficult since

energy is intangible — we can sense changes caused by energy, but not really the energy itself.

Several researchers have identified challenges to student understanding of energy concepts (Dri-

ver et. al, 1994; Trumper, 1990; Watts, 1983), including perceptions of energy as force, fuel or

fluid, as well as something that is ‘used up.’

Several studies have looked at conception of energy with respect to the complex concepts

of the greenhouse effect and global warming. In their study of elementary students’ understan-

ding of the greenhouse effect, Koulaidis and Christidou (1999) noted that students were more

likely to refer to the sun as a source of thermal energy, than a source of light energy (or radiati-

on). They also noticed that in many cases, students did not distinguish between the different

forms of energy yielded by the sun, resulting in terms such as ultraviolet rays, sun rays, and heat

rays essentially being used interchangeably. Several other studies of environmental issues and the

524 Kishore & Kisiel

greenhouse effect suggest similar confusion between thermal and light energy when considering

the role of the sun (Choi, Niyogi, Shepardson, and Charusombat, 2010; Henriksen and Jorde,

2001).

While there is some evidence to demonstrate student misconceptions regarding ‘sun’s

energy’, there is a dearth of published studies documenting students’ (or the general public’s)

conceptions of energy transformation (e.g. from electricity to heat or light) or more specifically

how people make sense of technology related to energy production (e.g. wind turbines,

photovoltaic technology) (Kisiel, 2008).

The purpose of this exploratory investigation was to add to this limited knowledge on

student understanding of alternative energy sources — specifically solar energy and photovoltaic

cells. Such knowledge should provide a useful baseline as we consider how best to promote pub-

lic understanding of science and environmental issues.

Methodology

Research Questions

This exploratory investigation sought to identify high school students’ underlying conceptions of

solar energy and photovoltaic technology. Two questions guided the inquiry: 1) To what extent

do students understand how solar (photovoltaic) cells work? and 2) To what extent do students

recognize the role of light energy in the production of electricity from solar cells?

Sample

A sample of 327 high school students from ten different sophomore Biology classes (student ages

14-15), and two different teachers, were invited to participate in the study, which was conducted

within a single Southern California high school. The student demographics in this school of

2,300, are similar to those of other schools in the region and represent a multi-ethnic community

comprising primarily of students of Latino (49%), white (35%), Asian (8%) and other (8%)

ethnicities (Filipino, African American, American Indian and Pacific Islanders), (CDE, 2010).

The targeted population for this study reflected boys (47%) and girls (53%) enrolled in both

advanced (46%) and general biology (54%) classes. The high school, located in southeast Los

Angeles County, serves a local middle class community, not unlike other communities

throughout Southern California. A small number of students are bussed to school, and about 11%

students are on the free/reduced price meal program suggesting that students come from

neighboring communities and belong to varied economic strata. This school might be considered

as a representation of the local community and a survey among these students likely reflects the

general thinking patterns consistent with many high school students in California.

The research project was introduced to students, and the necessary parental consent

forms and individual assent forms were provided, as per University Internal Review Board (IRB)

requirements. The necessary forms were collected over a few weeks, resulting in a final sample

of 196 students used for the study. Those students without parental consent were asked to

participate, as their responses would be useful for informing the co-author’s science instruction-

however, their comments were not incorporated into the data set used for the research project.

Energy as a topic is obvious in all content areas (earth, life and physical science) of the

science standards as mandated by the California Environmental Protection Agency (2007). Life

science standards (including biology) emphasize the role of sunlight as the energy source for the

formation of energy pyramids, food webs and ecosystems, as well as its role of sunlight in photo-

synthesis. The co-author of the investigation, one of the two participating teachers, has also

Perceptions of Solar Energy and Solar Cells 525

recently coupled discussion of solar energy and photovoltaics with her discussion of photosyn-

thesis in her high school biology. The choice of this teen population sprung from this innovative

curriculum choice and the desire to understand how students made sense of a topic not explicitly

expressed as part of the curriculum (up to that point.) It is important to note, however, that data

used for this study was collected several months prior to the instructional unit in the biology class

that includes discussion of photosynthesis. As such, the students surveyed would not have been

exposed to high school science curricula that promote understanding of solar energy or energy

transfer.

Data Collection

A combination of multiple choice and open-ended questions were used to assess student

knowledge and understanding about solar energy and solar cell technology. A seven-item survey,

including both multiple choice and open-ended questions, was administered to all students in all

participating students on the same day (See appendix for full survey.) During the survey, students

were directed to look at small solar cells (photovoltaic panels) that were placed at clearly visible

locations in both classrooms, to serve as a reference for the survey questions. An image of a solar

panel was also included on the questionnaire itself for further clarification. Several questions

were used to target expected misunderstandings, based in part on findings from an earlier study

of public understanding of solar energy (Kisiel, 2008) as well as related literature (Coyle, 2005;

Henriques, 2002; Solomon, 1985). Keeley, Eberle and Farrin (2005) used multiple-choice format

for their formative assessment probes for classroom teachers, with known or expected miscon-

ceptions as possible explanation choices. A similar pattern was used in this study to address

known misconceptions from earlier studies and classroom observations. Open-ended responses

were also used to help to clarify the sources of misconceptions, as well as allow for the exposure

of other possible areas of confusion few studies in this area of inquiry, such as those implemented

as part of the NEED project, have allowed for such student elaboration. This triangulation of

qualitative and quantitative data ultimately allows for greater validity and an interpretation of

findings more indicative of student understanding (Patton, 1990). A pilot survey was tested using

older students (11th and 12

th graders) on the campus who had already taken Biology. Responses

from these volunteers were used to clarify both multiple-choice and open-response questions and

ultimately improve the validity of the survey.

Analysis

Analysis of student responses included both quantitative and qualitative approaches. Data gener-

ated from multiple-choice questions resulted in descriptive statistics that included frequencies

and cross-tabulations (including chi-square analyses) that allowed for comparisons between sub-

groups (e.g. students with accurate vs. inaccurate conceptions). Responses for open-ended ques-

tions were examined via an iterative process to identify recurring patterns resulting in categoriza-

tion of student ideas (Patton, 1990). Some categories were similar to those used in previous stud-

ies (Kisiel, 2008) although new categories surfaced from the data. Repeated evaluation of desig-

nated categories, reorganization of categories and collaborative discussions between co-authors,

helped to validate the data. Qualitative data were initially coded by the lead author; these desig-

nations were then checked independently by the co-author, using the same category criteria. Dis-

agreements were re-examined and discussed, resulting in further refined criteria and consistency

across the data set. Once the range of responses was identified for each question, response frequencies were

calculated to provide a better understanding of common responses for this population. Because

526 Kishore & Kisiel

different students occasionally skipped different questions, the total number of useful responses

varied slightly for each question. Rather than completely dismiss any questionnaire that was not

completed in its entirety, which would result in a lower sample size overall, the researchers chose

to look at the effective sample size for each question. This approach allowed for capture of all

relevant responses for each question and resulted in percentage calculations that are more repre-

sentative of those students responding to particular questions. The effective sample size has been

reported for each question as part of the analysis.

Findings

Student Familiarity and Understanding of Photovoltaics

To ensure that students had a shared conception of ‘solar panels,’ a picture was provided to the

students at the start of the survey, and a small version of an actual solar panel was placed on dis-

play in the classroom. Students were initially asked whether they had ever seen a solar panel, and

if so, where they had seen it. Most students (94%) indicated that they had some familiarity with

solar cells. They reported seeing solar panels outdoors (on streets, deserts and beaches-40%), on

rooftops (38%), in previous classes (23%), in appliances such as garden lights and calculators

(10%), and in the media (15%).

A simple open-ended question “How do you think the solar panel works?” provided the

students an opportunity to describe in detail, what they know about solar panels. In many cases,

students did not provide complete descriptions of the mechanism, but rather key components or

steps. Several categories of responses were developed for this question, addressing a range of

student ideas (see Table 1). A small number of respondents (3%) provided accurate and detailed

explanations of the photovoltaic process light exciting the electrons to generate an electrical

current consistent with a full scientific explanation. A larger number (17%) of student provided a

more generalized, but essentially correct explanation, involving two key components: light (or

sun’s radiation) and the conversion of energy to electricity.

Most of the other responses suggested parts of the process, typically without a complete

mechanism. Note that these additional categories are not mutually exclusive, as students often

provided multiple ideas. For instance, numerous responses correctly identified one of the key

components of the photovoltaic mechanism, either the light (without mentioning electricity) or

the generation of electricity (without specifically mentioning light energy). Such responses,

though correct in part, did not explain the entire process. Approximately one third of the students

mentioned some kind of energy transformation (‘converts energy from sun’) while a similar pro-

portion of respondents mentioned energy absorption (‘takes in sun’s energy’) without referring to

a specific source or the final product of electricity. A smaller group (8%) of students suggested

that solar panels could be devices that stored energy and would run electrical appliances when

there is no sunlight.

The variety of responses from this initial question, and the different perceptions of sun as

an energy source led to a second categorization of student explanations. For this analysis, respon-

ses were coded to find out whether students understood that the photovoltaic panels relied

specifically on light energy from the sun rather than thermal (heat) energy to generate electricity.

Student responses ranged from mentioning light, heat, both heat and light or in most cases just

’sun energy’ in general. All responses were categorized into mutually exclusive groups (see Tab-

le 2).

Perceptions of Solar Energy and Solar Cells 527

Table 1. Student explanations of solar panels

Explanation Category Description Sample responses %

(N = 178)*

Photovoltaics Responses that specified

electron flow of light

energy to electricity.

Solar cells are made up of electrons

and when the sun’s rays hit them,

some electrons come loose….The

loose electrons … begin to move

around and it generates energy. This

energy is brought out of the panels

through wires and they go through

boxes where they are converted into

usable electricity-A72

3%

Light transformed to

electricity

Responses that

mentioned sunlight as

the source of energy that

transformed to

electricity.

Solar panels absorb sunlight and

convert it to electricity-B24

17%

Light energy as an

input

Responses that

mentioned the light

(photo) aspect.

It absorbs sunlight….-A57 16%

Electricity as an

outcome

Responses that

mentioned the electricity

(voltaics) aspect.

It feeds off the sun’s energy which

gives off electricity-A55

13%

Energy transformati-

on

Responses that

mentioned heat or

energy more generally

as being transformed.

I think solar panels collect the sun’s

rays and is able to convert that heat

into energy-B70

32%

Energy absorption Responses that

mentioned absorption of

energy generally.

They absorb energy from the sun-

A53

28%

Energy storage Responses that

mentioned solar panels

as storage devices.

The panels would store the sun’s rays

and use it later on as energy-B34

8%

Incoherent or

incomplete responses

Responses that did not

address the question

Provides energy-A59 5%

Note: Sample size reported in this table (and subsequent tables in this study) is based on those students

who effectively responded to the question. Blanks and illegible responses were not included in the sample

size.

528 Kishore & Kisiel

Responses that did not mention a source in their response or did not respond to the

question were excluded from the total number for percentage calculations resulting in an

effective sample size of 170. (This approach demonstrates the researcher choice to maximize

available responses for each question, as described earlier.)

Table 2. Student explanations categorized by energy type

Energy Type

Mentioned Examples

%

(N=170)

Light It absorb[s] sunlight and convert[s] it into energy-A44 41%

Heat It collects the suns heat rays and uses its heat as energy-

A71

8%

Light and Heat The solar cells on a solar panel absorb light and heat, and

the light and heat cause chemical reactions in the cells like

batteries. This produces electricity-B50

3%

Sun Solar panels take in the sun’s energy-B39 48%

For this alternate coding scheme, responses that mentioned sunlight, brightness or radia-

tion were coded as indicating a light source. A large number of students (41%, n=170) referred to

light as source, although it is important to note that not all of these students necessarily described

the complete photovoltaic process. Responses that referred to heat, warmth, or temperature were

categorized under the heat category (8%). Some of the responses (3%) specifically mentioned

both thermal and light energy being absorbed by the solar panels and such responses were placed

in the third category. Finally, explanations that mentioned ‘sun’s energy’ in a general sense were

placed under the ‘sun’ category. Nearly half (48%) of the responses used the general term ‘sun’s

energy’; given the open-ended nature of the question, and the lack of additional probing for this

paper-and-pencil survey, and it was difficult to say whether these students made the distinction

between the two aspects of solar energy.

The Role of Light or Heat

Student understanding of the energy source for photovoltaic cells was further probed by directing

student attention to practical applications and possible explanations. For instance, students were

given the prompt “Solar panels work better when there are clear skies. Why do you think so?”

with four possible responses: a) Because the solar panels absorb heat from the sun; b) Because

the solar panels absorb light from the sun; c) Because the solar panels absorb both heat and light

from the sun. d) Any other reason. About a third (36%) responded correctly indicating absorption

of light as the reason; a smaller number of students (13%) suggested that absorbing heat led to

better efficiency of solar panels during clear skies. However, more than half (58%) of the

students responded that both light and heat improved panel effectiveness, again suggesting an

underlying confusion or misconception of heat as a contributing factor in the function of

photovoltaic panels. A crosstab comparison revealed that students who correctly identified the

role of light in the initial open-ended question were more likely to answer this question correctly,

Perceptions of Solar Energy and Solar Cells 529

understanding that clear skies allowed for more light, which allowed solar panels to be more

productive [χ2(1) =6.62, p=0.01].

An additional question was developed to further understand misconceptions related to

heat as a possible factor in the efficiency of photovoltaic cells. Students were given a scenario

where hot air (via a hair dryer) was blown onto one solar panel, while cold air was blown on

another. They were then asked to predict which panel would ‘work better’ under those

conditions. They were also permitted to choose ‘both would work the same’ or ‘not sure’ as res-

ponses. Because thermal energy does not play a significant role in the efficiency of a

photovoltaic cell, the most accurate response would be ‘both would work the same.’ Yet only

15% of the students selected that correct option. Nearly half (51%) responded that the PV cell

with the hot air would work better; nearly one third indicated that they were not sure, and only a

few students (3%) suggested that the ‘cold air’ cell would work better. Furthermore, unlike the

question about clear skies, chi square analysis suggests that students who correctly identified the

role of light for solar panel function (in the initial question) were NOT any more likely to

recognize that the temperature of the air (i.e. heat) doesn’t really affect solar cell performance

[χ2(1)=0.0671, p=0.42].

The confusion of the role of heat and light was further demonstrated when students were

asked what time of day solar panels worked best. The intent was to see whether students

understood how the angle of incident light impacted the efficiency of photovoltaic panels.

Although 72% of students (n=192) reported correctly that ‘middle of the day’ was best, several

different rationales were provided. Analysis of these open-ended responses showed that nearly a

quarter (24%) of those who identified mid-day as being the best time made reference to the pro-

per angle of the sun, while another 24% simply reported light was brightest during that time.

Again, however, a significant number of students (22%) indicated that the heat of the sun (or heat

AND light) was greatest mid-day, thereby allowing the panels to work best then. And as with the

initial question about how panels worked in the first place, a large group of students simply

reported that the sun was strongest then (without explicit reference to angle, light, or heat). A

second chi-square analysis was conducted comparing responses to the optimal time for solar cell

function and responses to the initial question regarding the mechanism for solar cells. In this ca-

se, analysis showed that students who correctly used a photovoltaic explanation were more likely

to identify mid-day as when solar cells work best. [χ2(1)=4.52, p=.033].

Discussion

Findings from this study revealed familiarity and some understanding of photovoltaics among

high school students, although misconceptions and contradictions were apparent. While most

students understood that solar panels, like the ones shown on the survey and displayed in class,

allowed for the production of electricity, there seemed to be some confusion regarding the form

of energy that these panels absorbed for conversion to electricity. Light was featured in many

responses as the primary factor determining the efficiency of a photovoltaic cell, but many

students mentioned heat as an equally important factor.

The picture in the survey and the model placed in full view of the students was clearly a

photovoltaic cell; these we included to ensure that students were at least visually familiar with the

technology being discussed in the survey. It is conceivable, however, that students’ prior unders-

tanding of solar panels involved examples that worked through heat transfer. There are many

examples of solar technology that feature thermal energy. Solar water heaters installed on roof-

tops work on the thermal capacity of the sun to warm up small quantities of water pumped

through narrow tubes. Although these thermal ‘solar panels’ look quite different from the PV cell

panels, it is quite possible that this older conception may have contributed to students’ use of

530 Kishore & Kisiel

explanations involving thermal energy. There are other examples of thermal-based energy inno-

vations. For instance, mirror-based thermal systems can generate electricity by using focused heat

from the sun to converting water into steam, which then runs a turbine. Even more common is the

simple solar oven, a favorite study tool among students, that uses mirrors to concentrate sunlight

and provides enough heat to bake cookies. Students learn by extending patterns of understanding

to include new information. Recognizing the sun as a source of heat and light is an everyday

experience for students, but the idea of distinguishing light energy separate from the thermal

energy from the sun may be a difficult concept in itself (Colburn, 2007.)

Student explanations of the working of the solar panel ranged from detailed explanations

of electrons being excited and the production of electrical current, to simple conversions of the

sun energy into usable energy. Analysis of these explanations with specific attention to the source

of energy revealed more than half of the students referred to the general term of ‘sun’s energy’ as

being needed for solar panels to work, making it difficult to ascertain student understanding of

the correct form of energy utilized by photovoltaic panels. This dual and somewhat abstract natu-

re of solar energy makes it all the more difficult to clearly understand the technology of

photovoltaics.

Comparison of responses across questions revealed some apparent contradictions in

thought. While students who correctly provided photovoltaic explanations for solar cells initially

were just as likely to use heat explanations when asked about the effect of warm air on solar cells

(i.e the hair dryer scenario), these same students were more likely to recognize that mid-day is the

optimal time for working solar cells. This connection between solar cell function and angle of

sun, however, does not rule out a thermal explanation, since mid-day can also be seen as the time

of day when temperature is highest. It seems likely, then, that some of the students who

recognized the role of photovoltaics when asked about solar cells, created alternate explanations

when confronted with an additional variable (heat) that could be incorporated into an explanation

as well.

Even though students may recognize that light energy is needed for PV solar panels to

work, the complexities of this technology were not entirely apparent to students. Solar panels

were compared to storage batteries that could help people survive through cold and cloudy winter

days. These students suggested that the panels absorb heat or light from the sun during the day

and power electrical appliances through the night. One student even compared the panel to a so-

lar-powered flashlight. While solar cells, whether singular or in a panel array, essentially function

the same way, what happens to the electrical energy may vary depending on the application—the

electricity may be used immediately as a point source of energy, it may be transferred to the po-

wer ‘grid’, where it becomes available to multiple consumers, or it may be used to charge a

battery. Students’ variety of experiences with solar cells and solar panels lead to a variety of

conceptions as to how they work. Everyday explanations are developed to make sense of these

experiences in the absence of explicit instructional efforts. In some cases these self-developed,

common sense explanations are appropriate, in some cases they are not.

As described earlier, the conception of the sun as a source of different kinds of radiant

energy (e.g. visible light, ultraviolet radiation, infrared radiation/heat) has implications for stu-

dent understanding of several key undesirable environmental processes, including climate change

and the greenhouse effect, as well as possible solutions to these problems (Choi et al., 2010;

Henrikson and Jorde, 2001.) Yet changing the way students think about the ‘sun’s energy’ or

other areas of confusion related to solar energy may require them to think more deeply about the

nature of energy, and different energy forms. For instance, it may be difficult for students,

especially those who have grown up in southern California, to imagine sunlight without warmth.

Adjusting the way they think about the sun’s energy, while not automatic, will require students to

Perceptions of Solar Energy and Solar Cells 531

elaborate on their existing conceptual structures related to solar energy (or energy more broadly)

and possibly experience a conflict with their expectations (Driver et al., 1994; NRC, 2007). Such

misconceptions have to be drawn out, discussed and clarified to bring a change in student

“perceptions” whether that be a simple reorganization of concepts (e.g. ‘solar energy’ may

include both visible light and thermal energy both of which are forms of radiant energy) or a

more complex restructuring of their previously built knowledge framework (Henriques, 2002;

Liu & Ruiz, 2008, NRC 2007). By conducting some of the thought experiments described in the

survey (e.g. comparing the effects of hair dryers), students are may be able to expand their

conception of solar energy, allowing them to more effectively assess the efficiency of different

solar technologies under different conditions.

The investigation presented here is limited in its scope—additional studies are needed to

obtain a clearer picture of students’ conceptions of solar energy, and how solar panels work.

More direct clinical interviews, which would allow for probing and clarification of student res-

ponses, might be able to reduce some of the ambiguity reported by students participating in this

investigation. Furthermore, it is not clear to what extent these responses reflect a regional bias

and whether students located in different climate regions, or even communities or nations that

make greater use of solar technology, are likely to have significantly different responses.

Nevertheless, the investigation does provide an additional view, if only a snapshot, of the pub-

lic’s familiarity with solar technologies and potential areas of misunderstanding.

Students accumulate numerous bits of information in the course of their studies and daily

life experiences, but it is the overarching responsibility of the teachers to integrate such

experiences and explanations into the school science curriculum. Current content standards in

California, which drive science instruction, incorporate only limited discussion of renewable

energy within the basic disciplines of physics, chemistry, earth science and life science (CDE,

1998). Yet students in high school, beginning their training as members of a future workforce,

need the opportunity to understand how we use energy, and how we might curtail such use via

alternatives. Studies such as the one presented here, remind us that ‘going green’ means making

sure we clarify just what ‘green’ means, including an understanding of the science and technolo-

gy that are presented as alternatives to our current actions. Finding creative ways to integrate

such concepts into the classroom curriculum (e.g. discussion of photovoltaics in tandem with

photosynthesis) becomes a key responsibility of science educators charged with improving our

public’s scientific literacy.

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Bellflower Blvd, Long Beach, CA 90840, United States of America. E-mail: [email protected]

Please cite as: Kishore, P., & Kisiel, J. (2013). Exploring high school students’ perceptions of

solar energy and solar cells. International Journal of Environmental and Science Education, 8, 521-

534. doi: 10.12973/ijese.2013.216a

534 Kishore & Kisiel

Appendix: Student Questionnaire

Energy Survey

This questionnaire is for research purposes only. The answers will not be graded and will not in any

way affect your school grades. Anonymity will be maintained at all times. Answer the questions to the

best of your knowledge and do not worry about grammar and spelling.

1. Solar panels are made of several photovoltaic (solar) cells as shown below.

[image of solar panels was inserted here]

Have you ever seen one?

A. Yes

B. No

2. If you HAVE seen a solar panel (other than these examples), where did you

see it? (Try to describe the location and the purpose for which it might have been used.

If you’ve seen them in more than one place, describe those as well.)

3. How do you think the solar panel works? (Try to explain it as you would to a

friend)

4. Where did you learn about solar panels? (Check all that apply)

A. Magazines/books

B. School/classes

C. Internet

D. Visit to a solar-paneled building

E. Friends and family

F. Television

G. Other (Describe in the space below)

5. Solar panels work better when there are clear skies. Why do you think so?

A. Because the solar panels absorb heat from the sun

B. Because the solar panels absorb light from the sun

C. Because the solar panels absorb both heat and light from the sun

D. Any other reason (explain below):

6. a. When during the day do solar panels work best?

A. During sunrise and sunset

B. During the middle of the day

C. Solar panels work as well any time of the day

b. Why do you think so?

7. A hair dryer blows hot air on SOLAR CELL A; another hair dryer blows cold air on

SOLAR CELL B. Which SOLAR CELL do you think would work better under these

conditions?

A. Cell A

B. Cell B

C. Both would work about the same

D. Not sure